The present invention generally relates to a vehicle radiant heating control system. More specifically, the present invention relates to supplying heat to a vehicle cabin interior space using a radiant heating element in a vehicle having a 12 VDC battery.
Background Information
For many years, automotive vehicles have been provided with climate control systems (e.g., heating, ventilating and air conditioning (HVAC) systems) in order to provide a more comfortable environment for the driver and any passengers. Passenger compartments of vehicles have traditionally been warmed by circulating air such that it contacts a heater core associated with a coolant loop of an internal combustion engine. Thus, the heater core is normally heated by the engine coolant from the vehicle's engine. In cold conditions, when the vehicle is first started, the engine is cold. Thus, the engine coolant is also cold and is insufficient to warm the air entering the vehicle cabin. This results in a period of time in which the cabin remains below the desired cabin temperature.
In recent years, hybrid vehicles and electric vehicles have become more popular. Given the vehicle market trend toward hybrid vehicles and electric vehicles, new ways to generate cabin heat for occupants are being explored. As mentioned above, passenger compartments of vehicles have traditionally been warmed by circulating air such that it contacts a heater core. However, such a heater core would not be present in an electric vehicle. Also, even in the case of an internal combustion engine of a hybrid vehicle, it can often take a long time for a heater core to warm up on a very cold day. Thermally radiant electrical devices are often used as heating elements (e.g., heat lamps to keep food warm) and have been proposed for use in vehicles. For example, use of an infrared heater has been proposed in U.S. Pat. No. 3,619,555 to Bassett, Jr. (assigned to General Motors Corporation). However, it has been discovered that radiant heating elements are typically high-wattage devices powered by AC mains, which makes them less feasible for use in vehicles since vehicle electronics are usually powered by a 12 volt DC battery or other direct current battery source.